tools: add sensor node patch script

docs/API.md

@@ -396,7 +396,7 @@ Fields:
 |---|---:|---|
 | `id` | Yes | `relay_1` or `relay_2` |
 | `name` | No | User display name |
-| `enabled` | No | Configured enabled state |
+| `enabled` | No | Configured enabled state. When set to `false`, the relay output is forced OFF and future relay control requests are rejected with `relay_disabled`. |
 
 Returns the updated config.
 

docs/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+- Added standalone XIAO ESP32-C6 BNO086/MAX-M10S sensor-node firmware and a versioned RS485 telemetry contract without changing Cargo `/api/v1` or JBD/NimBLE behavior.
+
+## Unreleased
+
 ### Added
 - Cargo ESP local OTA firmware upload page at `/ota`.
 - Cargo ESP OTA API endpoint at `POST /api/v1/system/ota`.

docs/CONFIGURATION.md

@@ -69,6 +69,8 @@ HTTP endpoint:
 
     POST /api/v1/config/relay
 
+Disabled relays are forced OFF immediately, hidden from normal dashboard controls, and protected from `/api/v1/relay/set` commands until re-enabled.
+
 ## Temperature Sensor Configuration
 
 Temperature sensors use generic firmware IDs:

docs/README.md

@@ -53,5 +53,6 @@ The LILYGO T-Relay-S3 6-way board has been ordered as a future Cargo ESP candida
 Current development remains on the 2-channel relay board while the API and docs are prepared for output-count-agnostic operation.
 
 - `api-v1-audit.md` - Audit of legacy API paths vs `/api/v1` namespace.
+- `SENSOR_NODE_PROTOCOL.md` - XIAO ESP32-C6 BNO086/MAX-M10S RS485 telemetry contract.
 
 - `waveshare-5b-bringup-checklist.md` - Bench bring-up checklist for the Waveshare ESP32-S3 Touch LCD 5B dashboard.

docs/SENSOR_NODE_PROTOCOL.md

@@ -0,0 +1,17 @@
+# XIAO ESP32-C6 Sensor Node Protocol
+
+The XIAO sensor node reads the BNO086 and MAX-M10S and publishes vehicle telemetry over half-duplex RS485 at 115200 8-N-1, one JSON object per line. It owns no control state. Cargo remains the controller, HTTP server, and `/api/v1` source of truth; JBD/NimBLE behavior is unchanged.
+
+The expansion-board pins are D2 driver enable, D4 TX, and D5 RX. Only physical bus ends should be terminated. Confirm A/B polarity because vendor labels vary.
+
+## Schema version 1
+
+`sensor_status` includes `node_id`, `firmware_version`, `uptime_ms`, and:
+
+- `imu`: `online`, `valid`, `accuracy`, quaternion, yaw, pitch, and roll in degrees.
+- `gps`: `online`, `fix`, satellites, latitude, longitude, altitude meters, speed kph, course degrees, and structured UTC.
+
+Consumers must check `valid` or `fix` before displaying measurements and ignore unknown fields. The native breakout coordinate frame is reported initially; installation-specific axis remapping should follow physical calibration.
+
+This link does not replace dashboard-to-Cargo WiFi/HTTP. A future dashboard receiver may display this telemetry without moving relay, BMS, alarm, or configuration authority away from Cargo.
+

docs/dashboard-esp32s3.md

@@ -319,3 +319,14 @@ The diagnostics overlay shows dashboard version, uptime, heap, WiFi RSSI/IP, Car
 - Sends standard 11-bit functional request ID `0x7DF` and accepts ECU responses from `0x7E8` through `0x7EF`.
 - Diagnostics page shows TWAI state, coolant value, TX/RX counts, and last OBD status.
 - Overview coolant gauge shows `--°` until a valid OBD response is received.
+
+
+## Dashboard first-boot WiFi setup
+
+The ESP32-S3 dashboard no longer hardcodes Cargo ESP WiFi credentials or the Cargo API base URL. On first boot, it shows a touchscreen setup page where the user enters:
+
+- Cargo ESP WiFi SSID
+- Cargo ESP WiFi password
+- Cargo API base URL, for example `http://192.168.4.1`
+
+The dashboard saves these values in ESP32 Preferences/NVS and builds all `/api/v1` endpoint URLs at runtime. The boot screen also provides a Setup button for changing saved settings later.

firmware/esp32-s3-dashboard/dashboard_config.h

@@ -1,20 +1,8 @@
 #pragma once
 
-static const char *DASHBOARD_VERSION = "0.1.126-restore-boot-screen";
+static const char *DASHBOARD_VERSION = "0.1.127-first-boot-wifi";
 
-// Update these if your Cargo ESP AP credentials are different.
-static const char *CARGO_WIFI_SSID = "OverlandController";
-static const char *CARGO_WIFI_PASSWORD = "Ward1707";
-
-//static const char *CARGO_WIFI_SSID = "WardAP";
-//static const char *CARGO_WIFI_PASSWORD = "Ward5213";
-
-static const char *CARGO_API_STATUS_URL = "http://192.168.4.1/api/v1/status";
-static const char *CARGO_API_FAST_STATUS_URL = "http://192.168.4.1/api/v1/status?fields=battery,temps,relays";
-static const char *CARGO_API_SLOW_STATUS_URL = "http://192.168.4.1/api/v1/status?fields=network,system,config";
-static const char *CARGO_API_RELAY_SET_URL = "http://192.168.4.1/api/v1/relay/set";
-
-//static const char *CARGO_API_STATUS_URL = "http://192.168.88.181/api/v1/status";
-//static const char *CARGO_API_FAST_STATUS_URL = "http://192.168.88.181/api/v1/status?fields=battery,temps,relays";
-//static const char *CARGO_API_SLOW_STATUS_URL = "http://192.168.88.181/api/v1/status?fields=network,system,config";
-//static const char *CARGO_API_RELAY_SET_URL = "http://192.168.88.181/api/v1/relay/set";
+// First-boot defaults. Credentials are stored in Preferences/NVS after setup.
+static const char *DASHBOARD_DEFAULT_CARGO_WIFI_SSID = "OverlandController";
+static const char *DASHBOARD_DEFAULT_CARGO_WIFI_PASSWORD = "";
+static const char *DASHBOARD_DEFAULT_CARGO_API_BASE_URL = "http://192.168.4.1";

firmware/esp32-s3-dashboard/esp32-s3-dashboard.ino

@@ -1,5 +1,6 @@
 #include <Arduino.h>
 #include <WiFi.h>
+#include <Preferences.h>
 #include <HTTPClient.h>
 #include <ArduinoJson.h>
 #include <esp_display_panel.hpp>
@@ -16,6 +17,23 @@ using namespace esp_panel::drivers;
 using namespace esp_panel::board;
 
 static DashboardStatus status_model;
+
+static Preferences dashboard_preferences;
+static String cargo_wifi_ssid;
+static String cargo_wifi_password;
+static String cargo_api_base_url;
+static String cargo_api_status_url;
+static String cargo_api_fast_status_url;
+static String cargo_api_slow_status_url;
+static String cargo_api_relay_set_url;
+static bool dashboard_configured = false;
+
+static lv_obj_t *setup_ssid_textarea = nullptr;
+static lv_obj_t *setup_password_textarea = nullptr;
+static lv_obj_t *setup_api_textarea = nullptr;
+static lv_obj_t *setup_status_label = nullptr;
+static lv_obj_t *setup_keyboard = nullptr;
+
 static constexpr gpio_num_t OBD_CAN_TX_PIN = GPIO_NUM_15;
 static constexpr gpio_num_t OBD_CAN_RX_PIN = GPIO_NUM_16;
 static constexpr uint32_t OBD_REQUEST_ID = 0x7DF;
@@ -733,6 +751,7 @@ static void reset_battery_detail_widget_cache()
 
 static void update_battery_detail_widgets();
 static void show_boot_screen();
+static void show_dashboard_setup_screen();
 static void show_diagnostics_overlay();
 static void close_diagnostics_overlay();
 static void update_diagnostics_overlay();
@@ -1142,6 +1161,263 @@ static void update_relay_buttons()
     lvgl_port_unlock();
 }
 
+
+static String normalize_cargo_api_base_url(String value)
+{
+    value.trim();
+
+    if (value.length() == 0) {
+        value = DASHBOARD_DEFAULT_CARGO_API_BASE_URL;
+    }
+
+    if (!value.startsWith("http://") && !value.startsWith("https://")) {
+        value = "http://" + value;
+    }
+
+    while (value.endsWith("/")) {
+        value.remove(value.length() - 1);
+    }
+
+    return value;
+}
+
+static void rebuild_cargo_api_urls()
+{
+    cargo_api_base_url = normalize_cargo_api_base_url(cargo_api_base_url);
+    cargo_api_status_url = cargo_api_base_url + "/api/v1/status";
+    cargo_api_fast_status_url = cargo_api_base_url + "/api/v1/status?fields=battery,temps,relays";
+    cargo_api_slow_status_url = cargo_api_base_url + "/api/v1/status?fields=network,system,config";
+    cargo_api_relay_set_url = cargo_api_base_url + "/api/v1/relay/set";
+}
+
+static void load_dashboard_connection_config()
+{
+    dashboard_preferences.begin("dashcfg", false);
+
+    bool has_saved_ssid = dashboard_preferences.isKey("wifi_ssid");
+
+    cargo_wifi_ssid = dashboard_preferences.getString("wifi_ssid", DASHBOARD_DEFAULT_CARGO_WIFI_SSID);
+    cargo_wifi_password = dashboard_preferences.getString("wifi_pass", DASHBOARD_DEFAULT_CARGO_WIFI_PASSWORD);
+    cargo_api_base_url = dashboard_preferences.getString("api_base", DASHBOARD_DEFAULT_CARGO_API_BASE_URL);
+
+    rebuild_cargo_api_urls();
+
+    // Only skip setup after the user has explicitly saved settings.
+    dashboard_configured = has_saved_ssid;
+
+    Serial.print("Dashboard cargo SSID configured: ");
+    Serial.println(dashboard_configured ? "yes" : "no");
+    Serial.print("Dashboard cargo API base: ");
+    Serial.println(cargo_api_base_url);
+}
+
+static void save_dashboard_connection_config(const String &ssid, const String &password, const String &api_base)
+{
+    cargo_wifi_ssid = ssid;
+    cargo_wifi_password = password;
+    cargo_api_base_url = api_base;
+    rebuild_cargo_api_urls();
+
+    dashboard_preferences.putString("wifi_ssid", cargo_wifi_ssid);
+    dashboard_preferences.putString("wifi_pass", cargo_wifi_password);
+    dashboard_preferences.putString("api_base", cargo_api_base_url);
+
+    dashboard_configured = cargo_wifi_ssid.length() > 0;
+}
+
+static void setup_keyboard_event_cb(lv_event_t *event)
+{
+    lv_event_code_t code = lv_event_get_code(event);
+
+    if (code == LV_EVENT_READY || code == LV_EVENT_CANCEL || code == LV_EVENT_CLICKED) {
+        if (setup_keyboard != nullptr) {
+            lv_keyboard_set_textarea(setup_keyboard, nullptr);
+            lv_obj_add_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);
+        }
+    }
+}
+
+static void setup_textarea_event_cb(lv_event_t *event)
+{
+    lv_event_code_t code = lv_event_get_code(event);
+    lv_obj_t *target = lv_event_get_target(event);
+
+    if (code == LV_EVENT_FOCUSED || code == LV_EVENT_CLICKED) {
+        if (setup_keyboard != nullptr) {
+            lv_keyboard_set_textarea(setup_keyboard, target);
+            lv_obj_clear_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);
+        }
+    }
+}
+
+static lv_obj_t *create_setup_textarea(lv_obj_t *parent, const char *label_text, const String &value, int y, bool password)
+{
+    lv_obj_t *label = lv_label_create(parent);
+    lv_label_set_text(label, label_text);
+    lv_obj_set_style_text_color(label, lv_color_hex(0xDDE3EA), 0);
+    lv_obj_set_style_text_font(label, &lv_font_montserrat_26, 0);
+    lv_obj_align(label, LV_ALIGN_TOP_LEFT, 80, y);
+
+    lv_obj_t *textarea = lv_textarea_create(parent);
+    lv_obj_set_size(textarea, 760, 52);
+    lv_obj_align(textarea, LV_ALIGN_TOP_LEFT, 80, y + 32);
+    lv_textarea_set_one_line(textarea, true);
+    lv_textarea_set_text(textarea, value.c_str());
+    lv_textarea_set_password_mode(textarea, password);
+    lv_obj_set_style_text_font(textarea, &lv_font_montserrat_26, 0);
+    lv_obj_add_event_cb(textarea, setup_textarea_event_cb, LV_EVENT_ALL, nullptr);
+
+    return textarea;
+}
+
+static void setup_save_event_cb(lv_event_t *event)
+{
+    if (lv_event_get_code(event) != LV_EVENT_CLICKED) {
+        return;
+    }
+
+    if (setup_keyboard != nullptr) {
+        lv_keyboard_set_textarea(setup_keyboard, nullptr);
+        lv_obj_add_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);
+    }
+
+    String ssid = lv_textarea_get_text(setup_ssid_textarea);
+    String password = lv_textarea_get_text(setup_password_textarea);
+    String api_base = lv_textarea_get_text(setup_api_textarea);
+
+    ssid.trim();
+    api_base.trim();
+
+    if (ssid.length() == 0) {
+        if (setup_status_label != nullptr) {
+            lv_label_set_text(setup_status_label, "SSID is required.");
+        }
+        return;
+    }
+
+    save_dashboard_connection_config(ssid, password, api_base);
+
+    WiFi.disconnect(true);
+    was_wifi_connected = false;
+    overview_screen_created = false;
+    last_wifi_attempt_ms = 0;
+    last_status_poll_ms = 0;
+    last_metadata_poll_ms = 0;
+    metadata_refresh_requested = true;
+
+    lvgl_port_lock(-1);
+    if (dashboard_configured) {
+        show_boot_screen();
+    } else {
+        show_dashboard_setup_screen();
+    }
+    lvgl_port_unlock();
+
+    Serial.println("Dashboard connection settings saved.");
+}
+
+static void setup_reset_event_cb(lv_event_t *event)
+{
+    if (lv_event_get_code(event) != LV_EVENT_CLICKED) {
+        return;
+    }
+
+    if (setup_keyboard != nullptr) {
+        lv_keyboard_set_textarea(setup_keyboard, nullptr);
+        lv_obj_add_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);
+    }
+
+    dashboard_preferences.clear();
+    cargo_wifi_ssid = "";
+    cargo_wifi_password = "";
+    cargo_api_base_url = DASHBOARD_DEFAULT_CARGO_API_BASE_URL;
+    rebuild_cargo_api_urls();
+    dashboard_configured = false;
+
+    WiFi.disconnect(true);
+
+    lv_textarea_set_text(setup_ssid_textarea, "");
+    lv_textarea_set_text(setup_password_textarea, "");
+    lv_textarea_set_text(setup_api_textarea, cargo_api_base_url.c_str());
+
+    if (setup_status_label != nullptr) {
+        lv_label_set_text(setup_status_label, "Saved settings cleared.");
+    }
+}
+
+static void show_dashboard_setup_screen()
+{
+    lv_obj_t *screen = lv_scr_act();
+    lv_obj_clean(screen);
+    lv_obj_set_style_bg_color(screen, lv_color_hex(0x101418), 0);
+
+    lv_obj_t *title = lv_label_create(screen);
+    lv_label_set_text(title, "Dashboard Setup");
+    lv_obj_set_style_text_color(title, lv_color_hex(0xFFFFFF), 0);
+    lv_obj_set_style_text_font(title, &lv_font_montserrat_48, 0);
+    lv_obj_align(title, LV_ALIGN_TOP_MID, 0, 28);
+
+    lv_obj_t *subtitle = lv_label_create(screen);
+    lv_label_set_text(subtitle, "Enter Cargo ESP WiFi and API settings.");
+    lv_obj_set_style_text_color(subtitle, lv_color_hex(0xB8C0C8), 0);
+    lv_obj_set_style_text_font(subtitle, &lv_font_montserrat_26, 0);
+    lv_obj_align(subtitle, LV_ALIGN_TOP_MID, 0, 86);
+
+    setup_ssid_textarea = create_setup_textarea(screen, "Cargo WiFi SSID", cargo_wifi_ssid, 130, false);
+    setup_password_textarea = create_setup_textarea(screen, "Cargo WiFi Password", cargo_wifi_password, 220, true);
+    setup_api_textarea = create_setup_textarea(screen, "Cargo API Base URL", cargo_api_base_url, 310, false);
+
+    lv_obj_t *save_button = lv_btn_create(screen);
+    lv_obj_set_size(save_button, 210, 58);
+    lv_obj_align(save_button, LV_ALIGN_TOP_LEFT, 80, 408);
+    lv_obj_add_event_cb(save_button, setup_save_event_cb, LV_EVENT_CLICKED, nullptr);
+    lv_obj_t *save_label = lv_label_create(save_button);
+    lv_label_set_text(save_label, "Save");
+    lv_obj_center(save_label);
+
+    lv_obj_t *clear_button = lv_btn_create(screen);
+    lv_obj_set_size(clear_button, 210, 58);
+    lv_obj_align(clear_button, LV_ALIGN_TOP_LEFT, 310, 408);
+    lv_obj_add_event_cb(clear_button, setup_reset_event_cb, LV_EVENT_CLICKED, nullptr);
+    lv_obj_t *clear_label = lv_label_create(clear_button);
+    lv_label_set_text(clear_label, "Clear");
+    lv_obj_center(clear_label);
+
+    setup_status_label = lv_label_create(screen);
+    lv_label_set_text(setup_status_label, dashboard_configured ? "Settings loaded." : "First boot: setup required.");
+    lv_obj_set_style_text_color(setup_status_label, lv_color_hex(0xDDE3EA), 0);
+    lv_obj_set_style_text_font(setup_status_label, &lv_font_montserrat_26, 0);
+    lv_obj_set_width(setup_status_label, 420);
+    lv_label_set_long_mode(setup_status_label, LV_LABEL_LONG_WRAP);
+    lv_obj_align(setup_status_label, LV_ALIGN_TOP_LEFT, 548, 410);
+
+    lv_obj_t *done_button = lv_btn_create(screen);
+    lv_obj_set_size(done_button, 180, 48);
+    lv_obj_align(done_button, LV_ALIGN_BOTTOM_RIGHT, -32, -188);
+    lv_obj_add_event_cb(done_button, setup_keyboard_event_cb, LV_EVENT_CLICKED, nullptr);
+    lv_obj_t *done_label = lv_label_create(done_button);
+    lv_label_set_text(done_label, "Done");
+    lv_obj_center(done_label);
+
+    setup_keyboard = lv_keyboard_create(screen);
+    lv_obj_set_size(setup_keyboard, 1024, 180);
+    lv_obj_align(setup_keyboard, LV_ALIGN_BOTTOM_MID, 0, 0);
+    lv_obj_add_event_cb(setup_keyboard, setup_keyboard_event_cb, LV_EVENT_ALL, nullptr);
+    lv_obj_add_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);
+}
+
+static void setup_button_event_cb(lv_event_t *event)
+{
+    if (lv_event_get_code(event) != LV_EVENT_CLICKED) {
+        return;
+    }
+
+    lvgl_port_lock(-1);
+    show_dashboard_setup_screen();
+    lvgl_port_unlock();
+}
+
+
 static bool post_relay_state(const String &relay_id, bool state)
 {
     if (api_request_in_progress || WiFi.status() != WL_CONNECTED) {
@@ -1158,12 +1434,12 @@ static bool post_relay_state(const String &relay_id, bool state)
     serializeJson(request, payload);
 
     Serial.print("POST ");
-    Serial.println(CARGO_API_RELAY_SET_URL);
+    Serial.println(cargo_api_relay_set_url);
     Serial.println(payload);
 
     HTTPClient http;
     http.setTimeout(1200);
-    http.begin(CARGO_API_RELAY_SET_URL);
+    http.begin(cargo_api_relay_set_url);
     http.setReuse(false);
     http.addHeader("Connection", "close");
     http.addHeader("Content-Type", "application/json");
@@ -1280,6 +1556,10 @@ static void process_pending_relay_command()
 
 static void connect_wifi_if_needed()
 {
+    if (!dashboard_configured) {
+        return;
+    }
+
     if (WiFi.status() == WL_CONNECTED) {
         return;
     }
@@ -1291,10 +1571,10 @@ static void connect_wifi_if_needed()
     last_wifi_attempt_ms = millis();
 
     Serial.print("Connecting to Cargo ESP AP: ");
-    Serial.println(CARGO_WIFI_SSID);
+    Serial.println(cargo_wifi_ssid);
 
     WiFi.mode(WIFI_STA);
-    WiFi.begin(CARGO_WIFI_SSID, CARGO_WIFI_PASSWORD);
+    WiFi.begin(cargo_wifi_ssid.c_str(), cargo_wifi_password.c_str());
 }
 
 static void update_system_status_label()
@@ -1835,13 +2115,13 @@ static void poll_status_api()
     if (fast_status_refresh_requested || millis() - last_status_poll_ms >= 1500) {
         fast_status_refresh_requested = false;
         last_status_poll_ms = millis();
-        fetch_status_fields(CARGO_API_FAST_STATUS_URL, "fast status");
+        fetch_status_fields(cargo_api_fast_status_url.c_str(), "fast status");
     }
 
     if (metadata_refresh_requested || millis() - last_metadata_poll_ms >= 30000) {
         metadata_refresh_requested = false;
         last_metadata_poll_ms = millis();
-        fetch_status_fields(CARGO_API_SLOW_STATUS_URL, "slow status");
+        fetch_status_fields(cargo_api_slow_status_url.c_str(), "slow status");
     }
 }
 
@@ -1908,6 +2188,15 @@ static void show_boot_screen()
     lv_obj_set_width(api, 700);
     lv_obj_set_style_text_align(api, LV_TEXT_ALIGN_CENTER, 0);
     lv_obj_align(api, LV_ALIGN_CENTER, 0, 118);
+
+    lv_obj_t *setup_button = lv_btn_create(screen);
+    lv_obj_set_size(setup_button, 180, 54);
+    lv_obj_align(setup_button, LV_ALIGN_BOTTOM_MID, 0, -34);
+    lv_obj_add_event_cb(setup_button, setup_button_event_cb, LV_EVENT_CLICKED, nullptr);
+
+    lv_obj_t *setup_label = lv_label_create(setup_button);
+    lv_label_set_text(setup_label, "Setup");
+    lv_obj_center(setup_label);
 }
 
 static void create_overland_overview_screen()
@@ -2181,6 +2470,8 @@ void setup()
     Serial.println("Display: 1024x600");
     Serial.println("API Base: /api/v1");
 
+    load_dashboard_connection_config();
+
     Board *board = new Board();
     board->init();
 

firmware/esp32/overland-controller/overland-controller.ino

@@ -1249,11 +1249,20 @@ function renderConfigControls(data){
         <div class="configrow">
           <label>${r.id}</label>
           <input id="relayName${i}" placeholder="Relay name" oninput="markConfigFieldTouched('relayName${i}')">
-          <label>${r.enabled?"Enabled":"Disabled"}</label>
+          <label class="tempCheck">
+            <input id="relayEnabled${i}" type="checkbox" onchange="markConfigFieldTouched('relayEnabled${i}')">
+            Enabled
+          </label>
         </div>`).join("");
     }
 
-    relays.forEach((r,i)=>setConfigValue("relayName"+i,r.name||""));
+    relays.forEach((r,i)=>{
+      setConfigValue("relayName"+i,r.name||"");
+      const enabled=$("relayEnabled"+i);
+      if(enabled && !configTouched["relayEnabled"+i] && document.activeElement!==enabled){
+        enabled.checked=!!r.enabled;
+      }
+    });
   }
 
   setConfigValue("tempEnabledCount", temps.filter(t=>t.enabled).length);
@@ -1359,8 +1368,8 @@ async function saveRelayConfig(){
   const relays=data.config?.relays||[];
 
   for(let i=0;i<relays.length;i++){
-    const name=$("relayName"+i)?.value.trim();
-    if(!name) continue;
+    const name=$("relayName"+i)?.value.trim() || relays[i].name || relays[i].id;
+    const enabled=$("relayEnabled"+i)?.checked ?? relays[i].enabled;
 
     await fetch(api("/config/relay"),{
       method:"POST",
@@ -1368,14 +1377,14 @@ async function saveRelayConfig(){
       body:JSON.stringify({
         id:relays[i].id,
         name:name,
-        enabled:relays[i].enabled
+        enabled:enabled
       })
     });
   }
 
   await fetch(api("/config/save"),{method:"POST"});
   await load();
-  alert("Relay names saved");
+  alert("Relay settings saved");
 }
 
 async function saveTempConfig(){
@@ -1543,9 +1552,19 @@ String staPasswords[MAX_WIFI_NETWORKS];
 int staPriorities[MAX_WIFI_NETWORKS];
 int wifiNetworkCount = 0;
 String activeStaSsid = "";
+bool staAttemptTried[MAX_WIFI_NETWORKS] = {false, false, false};
+bool staConnectInProgress = false;
+int activeStaAttemptIndex = -1;
+unsigned long staConnectAttemptStarted = 0;
 unsigned long lastStaReconnectAttempt = 0;
+const unsigned long STA_CONNECT_TIMEOUT_MS = 8000;
 const unsigned long STA_RECONNECT_INTERVAL_MS = 30000;
 
+void resetStaAttemptRound();
+bool beginNextStaWifiAttempt();
+void connectStaWifi();
+void maintainStaWifi();
+
 void loadWifiConfig() {
     wifiPrefs.begin("wifi", true);
 
@@ -2110,85 +2129,110 @@ int findNextWifiIndexByPriority(bool tried[]) {
     return bestIndex;
 }
 
+void resetStaAttemptRound() {
+    for (int i = 0; i < MAX_WIFI_NETWORKS; i++) {
+        staAttemptTried[i] = false;
+    }
+    staConnectInProgress = false;
+    activeStaAttemptIndex = -1;
+}
+
+bool beginNextStaWifiAttempt() {
+    if (wifiNetworkCount <= 0) {
+        Serial.println("STA WiFi not configured.");
+        return false;
+    }
+
+    int i = findNextWifiIndexByPriority(staAttemptTried);
+    if (i < 0) {
+        return false;
+    }
+
+    staAttemptTried[i] = true;
+    activeStaAttemptIndex = i;
+    activeStaSsid = "";
+
+    Serial.print("Starting non-blocking STA WiFi attempt priority ");
+    Serial.print(staPriorities[i]);
+    Serial.print(" to: ");
+    Serial.println(staSsids[i]);
+
+    WiFi.disconnect(false, false);
+    WiFi.mode(WIFI_AP_STA);
+    WiFi.begin(staSsids[i].c_str(), staPasswords[i].c_str());
+
+    staConnectAttemptStarted = millis();
+    staConnectInProgress = true;
+    return true;
+}
+
 void connectStaWifi() {
     if (wifiNetworkCount <= 0) {
         Serial.println("STA WiFi not configured.");
         return;
     }
 
-    WiFi.disconnect(false);
-    activeStaSsid = "";
+    resetStaAttemptRound();
+    lastStaReconnectAttempt = millis();
 
-    bool tried[MAX_WIFI_NETWORKS] = {false, false, false};
-
-    for (int attempt = 0; attempt < wifiNetworkCount; attempt++) {
-        int i = findNextWifiIndexByPriority(tried);
-
-        if (i < 0) {
-            break;
-        }
-
-        tried[i] = true;
-
-        Serial.print("Connecting STA WiFi priority ");
-        Serial.print(staPriorities[i]);
-        Serial.print(" to: ");
-        Serial.println(staSsids[i]);
-
-        WiFi.disconnect(false, false);
-        delay(500);
-        WiFi.mode(WIFI_AP_STA);
-        delay(250);
-
-        WiFi.begin(staSsids[i].c_str(), staPasswords[i].c_str());
-
-        unsigned long start = millis();
-        while (WiFi.status() != WL_CONNECTED && millis() - start < 8000) {
-            server.handleClient();
-            oledLoop();
-            delay(100);
-            Serial.print(".");
-        }
-
-        Serial.println();
-
-        if (WiFi.status() == WL_CONNECTED) {
-            activeStaSsid = staSsids[i];
-            Serial.println("STA WiFi connected");
-            Serial.print("STA SSID: ");
-            Serial.println(activeStaSsid);
-            Serial.print("STA IP: ");
-            Serial.println(WiFi.localIP());
-            return;
-        }
-
-        wl_status_t status = WiFi.status();
-        Serial.print("STA WiFi attempt failed. Status: ");
-        Serial.println((int)status);
-
-        wifi_ap_record_t apInfo;
-        if (esp_wifi_sta_get_ap_info(&apInfo) == ESP_OK) {
-            Serial.print("Connected AP RSSI: ");
-            Serial.println(apInfo.rssi);
-        } else {
-            Serial.println("No AP association info available.");
-        }
+    if (!beginNextStaWifiAttempt()) {
+        Serial.println("No saved STA WiFi networks available. AP remains available.");
     }
-
-    Serial.println("All STA WiFi attempts failed. AP remains available.");
 }
 
 void maintainStaWifi() {
     if (wifiNetworkCount <= 0) return;
 
-    if (WiFi.status() == WL_CONNECTED) return;
+    if (WiFi.status() == WL_CONNECTED) {
+        if (activeStaSsid.length() == 0) {
+            if (activeStaAttemptIndex >= 0 && activeStaAttemptIndex < wifiNetworkCount) {
+                activeStaSsid = staSsids[activeStaAttemptIndex];
+            } else {
+                activeStaSsid = WiFi.SSID();
+            }
+
+            Serial.println("STA WiFi connected");
+            Serial.print("STA SSID: ");
+            Serial.println(activeStaSsid);
+            Serial.print("STA IP: ");
+            Serial.println(WiFi.localIP());
+        }
+
+        staConnectInProgress = false;
+        activeStaAttemptIndex = -1;
+        return;
+    }
+
+    if (staConnectInProgress) {
+        if (millis() - staConnectAttemptStarted < STA_CONNECT_TIMEOUT_MS) {
+            return;
+        }
+
+        Serial.print("STA WiFi attempt timed out. Status: ");
+        Serial.println((int)WiFi.status());
+
+        WiFi.disconnect(false, false);
+        staConnectInProgress = false;
+        activeStaAttemptIndex = -1;
+
+        if (beginNextStaWifiAttempt()) {
+            return;
+        }
+
+        Serial.println("All STA WiFi attempts failed. AP remains available.");
+        resetStaAttemptRound();
+        lastStaReconnectAttempt = millis();
+        return;
+    }
+
+    activeStaSsid = "";
 
     if (millis() - lastStaReconnectAttempt < STA_RECONNECT_INTERVAL_MS) return;
 
+    Serial.println("STA WiFi disconnected. Trying saved networks by priority in background...");
+    resetStaAttemptRound();
     lastStaReconnectAttempt = millis();
-
-    Serial.println("STA WiFi disconnected. Trying saved networks by priority...");
-    connectStaWifi();
+    beginNextStaWifiAttempt();
 }
 
 void printNetworkStatus() {
@@ -2643,9 +2687,19 @@ void sendError(Stream& output, const char* message) {
 
 int findRelayConfigIndex(const String& id);
 
+bool relayExistsAndAvailable(const String& relayId) {
+    int index = findRelayConfigIndex(relayId);
+    return index >= 0 && appConfig.relays[index].available;
+}
+
+bool relayIsEnabled(const String& relayId) {
+    int index = findRelayConfigIndex(relayId);
+    return index >= 0 && appConfig.relays[index].enabled;
+}
+
 bool setRelayById(const String& relayId, bool enabled) {
     int index = findRelayConfigIndex(relayId);
-    if (index < 0 || !appConfig.relays[index].available) {
+    if (index < 0 || !appConfig.relays[index].available || !appConfig.relays[index].enabled) {
         return false;
     }
 
@@ -3651,7 +3705,13 @@ void handleUpdateRelayConfig() {
     }
 
     if (doc["name"].is<String>()) appConfig.relays[index].name = doc["name"].as<String>();
-    if (doc["enabled"].is<bool>()) appConfig.relays[index].enabled = doc["enabled"].as<bool>();
+    if (doc["enabled"].is<bool>()) {
+        appConfig.relays[index].enabled = doc["enabled"].as<bool>();
+        if (!appConfig.relays[index].enabled) {
+            relays.state[index] = false;
+            updateRelayOutputs();
+        }
+    }
 
     sendOkConfig();
 }
@@ -3994,10 +4054,18 @@ void handleSetRelayPost() {
     bool state = doc["state"] | false;
 
     unsigned long applyStartMs = millis();
-    if (!setRelayById(relayId, state)) {
+    if (!relayExistsAndAvailable(relayId)) {
         server.send(404, "application/json", "{\"ok\":false,\"error\":\"unknown_relay\"}");
         return;
     }
+    if (!relayIsEnabled(relayId)) {
+        server.send(409, "application/json", "{\"ok\":false,\"error\":\"relay_disabled\"}");
+        return;
+    }
+    if (!setRelayById(relayId, state)) {
+        server.send(409, "application/json", "{\"ok\":false,\"error\":\"relay_disabled\"}");
+        return;
+    }
     unsigned long appliedMs = millis() - applyStartMs;
 
     DynamicJsonDocument response(512);
@@ -4052,10 +4120,18 @@ void handleGenericRelayRoute() {
         return;
     }
 
-    if (!setRelayById(relayId, enabled)) {
+    if (!relayExistsAndAvailable(relayId)) {
         server.send(404, "application/json", "{\"ok\":false,\"error\":\"unknown_relay\"}");
         return;
     }
+    if (!relayIsEnabled(relayId)) {
+        server.send(409, "application/json", "{\"ok\":false,\"error\":\"relay_disabled\"}");
+        return;
+    }
+    if (!setRelayById(relayId, enabled)) {
+        server.send(409, "application/json", "{\"ok\":false,\"error\":\"relay_disabled\"}");
+        return;
+    }
 
     DynamicJsonDocument doc(512);
     doc["ok"] = true;
@@ -4206,6 +4282,7 @@ void setup() {
 
 void loop() {
     server.handleClient();
+    oledLoop();
 
     maintainStaWifi();
 

firmware/xiao-esp32c6-sensor-node/README.md

@@ -0,0 +1,15 @@
+# XIAO ESP32-C6 Sensor Node
+
+This Arduino sketch reads a BNO086 IMU and MAX-M10S GPS and publishes versioned, newline-delimited JSON over the Seeed RS485 expansion board. It produces vehicle telemetry only; Cargo remains the controller and `/api/v1` authority.
+
+| Function | XIAO pin |
+| --- | --- |
+| RS485 DE / TX / RX | D2 / D4 / D5 |
+| BNO086 SDA / SCL | D7 / D8 |
+| GPS TX to XIAO RX | D9 |
+| GPS RX from XIAO TX | D10 |
+
+Power both sensors from 3.3V with shared ground. Required Arduino libraries are Adafruit BNO08x, TinyGPSPlus, and ArduinoJson 6.x. Enable **USB CDC On Boot** for diagnostics. GPS uses hardware UART0 and RS485 uses hardware UART1.
+
+The node sends `sensor_status` at 115200 baud every 200 ms. See `docs/SENSOR_NODE_PROTOCOL.md`. The initial firmware is transmit-only; add a dashboard receiver after bench-testing the node, RS485 polarity, and sensor axes.
+

firmware/xiao-esp32c6-sensor-node/gps.cpp

@@ -0,0 +1,19 @@
+#include <TinyGPSPlus.h>
+#include "gps.h"
+#include "sensor_node_config.h"
+namespace { TinyGPSPlus parser; }
+
+void initGps(HardwareSerial& serial) { serial.begin(GPS_BAUD, SERIAL_8N1, GPS_RX_PIN, GPS_TX_PIN); }
+void updateGps(HardwareSerial& serial, GpsState& s) {
+    while (serial.available()) { s.lastByteMs = millis(); parser.encode(serial.read()); }
+    s.online = s.lastByteMs && millis() - s.lastByteMs <= SENSOR_STALE_MS;
+    s.fix = parser.location.isValid() && parser.location.age() <= SENSOR_STALE_MS;
+    s.satellites = parser.satellites.isValid() ? parser.satellites.value() : 0;
+    if (parser.location.isValid()) { s.latitude = parser.location.lat(); s.longitude = parser.location.lng(); }
+    if (parser.altitude.isValid()) s.altitudeMeters = parser.altitude.meters();
+    if (parser.speed.isValid()) s.speedKph = parser.speed.kmph();
+    if (parser.course.isValid()) s.courseDegrees = parser.course.deg();
+    if (parser.date.isValid()) { s.year = parser.date.year(); s.month = parser.date.month(); s.day = parser.date.day(); }
+    if (parser.time.isValid()) { s.hour = parser.time.hour(); s.minute = parser.time.minute(); s.second = parser.time.second(); }
+}
+

firmware/xiao-esp32c6-sensor-node/gps.h

@@ -0,0 +1,6 @@
+#pragma once
+#include <HardwareSerial.h>
+#include "sensor_state.h"
+void initGps(HardwareSerial& serial);
+void updateGps(HardwareSerial& serial, GpsState& state);
+

firmware/xiao-esp32c6-sensor-node/imu.cpp

@@ -0,0 +1,39 @@
+#include <Adafruit_BNO08x.h>
+#include <Wire.h>
+#include <math.h>
+#include "imu.h"
+#include "sensor_node_config.h"
+
+namespace {
+Adafruit_BNO08x bno086(-1);
+sh2_SensorValue_t value;
+bool initialized = false;
+float degrees(float r) { return r * 180.0f / PI; }
+void updateEuler(ImuState& s) {
+    float sinr = 2 * (s.real * s.i + s.j * s.k);
+    float cosr = 1 - 2 * (s.i * s.i + s.j * s.j);
+    s.rollDegrees = degrees(atan2f(sinr, cosr));
+    float sinp = 2 * (s.real * s.j - s.k * s.i);
+    s.pitchDegrees = degrees(fabsf(sinp) >= 1 ? copysignf(PI / 2, sinp) : asinf(sinp));
+    float siny = 2 * (s.real * s.k + s.i * s.j);
+    float cosy = 1 - 2 * (s.j * s.j + s.k * s.k);
+    s.yawDegrees = degrees(atan2f(siny, cosy));
+}
+}
+
+bool initImu() {
+    Wire.begin(BNO086_SDA_PIN, BNO086_SCL_PIN);
+    initialized = bno086.begin_I2C(BNO086_I2C_ADDRESS, &Wire);
+    if (initialized) initialized = bno086.enableReport(SH2_ROTATION_VECTOR, IMU_REPORT_INTERVAL_US);
+    return initialized;
+}
+
+void updateImu(ImuState& s) {
+    s.online = initialized;
+    if (!initialized || !bno086.getSensorEvent(&value) || value.sensorId != SH2_ROTATION_VECTOR) return;
+    s.i = value.un.rotationVector.i; s.j = value.un.rotationVector.j;
+    s.k = value.un.rotationVector.k; s.real = value.un.rotationVector.real;
+    s.accuracy = value.status; s.valid = true; s.lastUpdateMs = millis();
+    updateEuler(s);
+}
+

firmware/xiao-esp32c6-sensor-node/imu.h

@@ -0,0 +1,5 @@
+#pragma once
+#include "sensor_state.h"
+bool initImu();
+void updateImu(ImuState& state);
+

firmware/xiao-esp32c6-sensor-node/rs485_transport.cpp

@@ -0,0 +1,30 @@
+#include <ArduinoJson.h>
+#include "rs485_transport.h"
+#include "sensor_node_config.h"
+
+void initRs485(HardwareSerial& serial) {
+    pinMode(RS485_DE_PIN, OUTPUT); digitalWrite(RS485_DE_PIN, LOW);
+    serial.begin(RS485_BAUD, SERIAL_8N1, RS485_RX_PIN, RS485_TX_PIN);
+}
+
+void publishSensorStatus(HardwareSerial& serial, const ImuState& imu, const GpsState& gps) {
+    StaticJsonDocument<1024> doc;
+    doc["type"] = "sensor_status"; doc["schema_version"] = SENSOR_NODE_SCHEMA_VERSION;
+    doc["node_id"] = SENSOR_NODE_NAME; doc["firmware_version"] = SENSOR_NODE_FIRMWARE_VERSION;
+    doc["uptime_ms"] = millis();
+    JsonObject i = doc.createNestedObject("imu");
+    i["online"] = imu.online; i["valid"] = imu.valid && millis() - imu.lastUpdateMs <= SENSOR_STALE_MS;
+    i["accuracy"] = imu.accuracy;
+    JsonObject q = i.createNestedObject("quaternion"); q["i"] = imu.i; q["j"] = imu.j; q["k"] = imu.k; q["real"] = imu.real;
+    i["yaw_degrees"] = imu.yawDegrees; i["pitch_degrees"] = imu.pitchDegrees; i["roll_degrees"] = imu.rollDegrees;
+    JsonObject g = doc.createNestedObject("gps");
+    g["online"] = gps.online; g["fix"] = gps.fix; g["satellites"] = gps.satellites;
+    g["latitude"] = gps.latitude; g["longitude"] = gps.longitude; g["altitude_meters"] = gps.altitudeMeters;
+    g["speed_kph"] = gps.speedKph; g["course_degrees"] = gps.courseDegrees;
+    JsonObject utc = g.createNestedObject("utc"); utc["year"] = gps.year; utc["month"] = gps.month; utc["day"] = gps.day;
+    utc["hour"] = gps.hour; utc["minute"] = gps.minute; utc["second"] = gps.second;
+    digitalWrite(RS485_DE_PIN, HIGH); delayMicroseconds(20);
+    serializeJson(doc, serial); serial.write('\n'); serial.flush();
+    digitalWrite(RS485_DE_PIN, LOW);
+}
+

firmware/xiao-esp32c6-sensor-node/rs485_transport.h

@@ -0,0 +1,6 @@
+#pragma once
+#include <HardwareSerial.h>
+#include "sensor_state.h"
+void initRs485(HardwareSerial& serial);
+void publishSensorStatus(HardwareSerial& serial, const ImuState& imu, const GpsState& gps);
+

firmware/xiao-esp32c6-sensor-node/sensor_node_config.h

@@ -0,0 +1,20 @@
+#pragma once
+#include <Arduino.h>
+
+#define SENSOR_NODE_NAME "xiao_c6_sensor_node"
+#define SENSOR_NODE_FIRMWARE_VERSION "0.1.0"
+#define SENSOR_NODE_SCHEMA_VERSION 1
+#define RS485_DE_PIN D2
+#define RS485_TX_PIN D4
+#define RS485_RX_PIN D5
+#define BNO086_SDA_PIN D7
+#define BNO086_SCL_PIN D8
+#define GPS_RX_PIN D9
+#define GPS_TX_PIN D10
+#define BNO086_I2C_ADDRESS 0x4A
+#define GPS_BAUD 9600
+#define RS485_BAUD 115200
+#define IMU_REPORT_INTERVAL_US 20000
+#define TELEMETRY_INTERVAL_MS 200
+#define SENSOR_STALE_MS 2000
+

firmware/xiao-esp32c6-sensor-node/sensor_state.h

@@ -0,0 +1,21 @@
+#pragma once
+#include <Arduino.h>
+
+struct ImuState {
+    bool online = false, valid = false;
+    uint8_t accuracy = 0;
+    float i = 0, j = 0, k = 0, real = 1;
+    float yawDegrees = 0, pitchDegrees = 0, rollDegrees = 0;
+    unsigned long lastUpdateMs = 0;
+};
+
+struct GpsState {
+    bool online = false, fix = false;
+    uint32_t satellites = 0;
+    double latitude = 0, longitude = 0, altitudeMeters = 0;
+    double speedKph = 0, courseDegrees = 0;
+    uint16_t year = 0;
+    uint8_t month = 0, day = 0, hour = 0, minute = 0, second = 0;
+    unsigned long lastByteMs = 0;
+};
+

firmware/xiao-esp32c6-sensor-node/xiao-esp32c6-sensor-node.ino

@@ -0,0 +1,28 @@
+#include <Arduino.h>
+#include "gps.h"
+#include "imu.h"
+#include "rs485_transport.h"
+#include "sensor_node_config.h"
+
+HardwareSerial gpsSerial(0), rs485Serial(1);
+ImuState imuState;
+GpsState gpsState;
+unsigned long lastTelemetryMs = 0;
+
+void setup() {
+    Serial.begin(115200); delay(250);
+    Serial.println("XIAO ESP32-C6 sensor node booting");
+    initGps(gpsSerial); initRs485(rs485Serial);
+    imuState.online = initImu();
+    Serial.println(imuState.online ? "BNO086 ready" : "BNO086 not detected");
+}
+
+void loop() {
+    updateGps(gpsSerial, gpsState); updateImu(imuState);
+    unsigned long now = millis();
+    if (now - lastTelemetryMs >= TELEMETRY_INTERVAL_MS) {
+        publishSensorStatus(rs485Serial, imuState, gpsState); lastTelemetryMs = now;
+    }
+    delay(1);
+}
+

run_tests.py

@@ -4,6 +4,7 @@ import sys
 
 COMMANDS = [
     [sys.executable, "-m", "pytest", "tests/test_http_api_contract.py"],
+    [sys.executable, "-m", "pytest", "tests/test_xiao_sensor_node_contract.py"],
 ]
 
 

tests/test_dashboard_source_contract.py

@@ -0,0 +1,17 @@
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+DASHBOARD = ROOT / "firmware" / "esp32-s3-dashboard" / "esp32-s3-dashboard.ino"
+
+
+def test_setup_done_button_event_is_handled():
+    source = DASHBOARD.read_text()
+
+    callback_start = source.index("static void setup_keyboard_event_cb")
+    callback_end = source.index("static void setup_textarea_event_cb", callback_start)
+    callback = source[callback_start:callback_end]
+
+    assert "LV_EVENT_CLICKED" in callback
+    assert "lv_obj_add_flag(setup_keyboard, LV_OBJ_FLAG_HIDDEN);" in callback
+    assert "lv_obj_add_event_cb(done_button, setup_keyboard_event_cb, LV_EVENT_CLICKED" in source

tests/test_http_api_contract.py

@@ -248,6 +248,8 @@ def test_relay_set_contract_fixtures_and_firmware_errors():
     source = firmware_source()
     assert '"invalid_json"' in source
     assert '"unknown_relay"' in source
+    assert "relay_disabled" in source
+    assert "relayIsEnabled" in source
 
 
 def test_relay_api_is_output_count_agnostic():
@@ -259,6 +261,7 @@ def test_relay_api_is_output_count_agnostic():
     assert 'relay["hardware_channel"] = appConfig.relays[i].hardwareChannel;' in source
     assert 'relay["available"] = appConfig.relays[i].available;' in source
     assert 'relays.state[index] = enabled;' in source
+    assert '!appConfig.relays[index].enabled' in source
     assert 'relays.relay1' not in source
     assert 'relays.relay2' not in source
 

tests/test_xiao_sensor_node_contract.py

@@ -0,0 +1,27 @@
+import re
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+NODE = ROOT / "firmware" / "xiao-esp32c6-sensor-node"
+def source(name): return (NODE / name).read_text()
+
+def test_wiring_matches_assembly():
+    config = source("sensor_node_config.h")
+    expected = {"RS485_DE_PIN":"D2", "RS485_TX_PIN":"D4", "RS485_RX_PIN":"D5",
+                "BNO086_SDA_PIN":"D7", "BNO086_SCL_PIN":"D8", "GPS_RX_PIN":"D9", "GPS_TX_PIN":"D10"}
+    for name, pin in expected.items(): assert re.search(rf"#define\s+{name}\s+{pin}\b", config)
+
+def test_transport_contract():
+    text = source("rs485_transport.cpp")
+    for token in ['doc["type"] = "sensor_status"', 'doc["schema_version"]', 'createNestedObject("imu")', 'createNestedObject("gps")', "serial.write('\\n')", "serial.flush()"]:
+        assert token in text
+
+def test_loop_is_non_blocking():
+    loop = source("xiao-esp32c6-sensor-node.ino").split("void loop()", 1)[1]
+    assert "updateGps" in loop and "updateImu" in loop and "TELEMETRY_INTERVAL_MS" in loop
+    assert not re.search(r"delay\((?:[2-9]|[1-9]\d+)\)", loop)
+
+def test_node_does_not_take_cargo_or_ble_authority():
+    combined = "\n".join(p.read_text() for p in NODE.glob("*.*"))
+    assert "NimBLE" not in combined and "JBD" not in combined and "server.on(" not in combined
+

tools/apply_xiao_sensor_node_patch.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+PATCH_COMMIT="a701059"
+
+repo_root="$(git rev-parse --show-toplevel)"
+cd "$repo_root"
+
+if [[ -n "$(git status --porcelain)" ]]; then
+    echo "Refusing to edit a dirty working tree." >&2
+    exit 1
+fi
+
+if ! git cat-file -e "${PATCH_COMMIT}^{commit}" 2>/dev/null; then
+    git fetch origin
+fi
+
+if ! git merge-base --is-ancestor "$PATCH_COMMIT" HEAD; then
+    git cherry-pick "$PATCH_COMMIT"
+else
+    echo "XIAO sensor-node patch is already applied."
+fi
+
+if [[ ! -f .venv/bin/activate ]]; then
+    echo "Missing .venv/bin/activate; create the project virtual environment first." >&2
+    exit 1
+fi
+
+source .venv/bin/activate
+python run_tests.py
+
+git add -A
+if ! git diff --cached --quiet; then
+    git commit -m "firmware: apply XIAO C6 sensor node patch"
+fi
+
+branch="$(git branch --show-current)"
+if [[ -z "$branch" ]]; then
+    echo "Cannot push from detached HEAD." >&2
+    exit 1
+fi
+git push origin "$branch"